ipv6: Refactor find_match

find_match primarily needs a fib6_nh (and fib6_flags which it passes
through to rt6_score_route). Move fib6_check_expired up to the call
sites so find_match is only called for relevant entries. Remove the
match argument which is mostly a pass through and use the return
boolean to decide if match gets set in the call sites.

The end result is a helper that can be called per fib6_nh struct
which is needed once fib entries reference nexthop objects that
have more than one fib6_nh.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 22d1933..200bd5b 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -632,25 +632,22 @@ static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
        return m;
 }
 
-static struct fib6_info *find_match(struct fib6_info *rt, int oif, int strict,
-                                  int *mpri, struct fib6_info *match,
-                                  bool *do_rr)
+static bool find_match(struct fib6_nh *nh, u32 fib6_flags,
+                      int oif, int strict, int *mpri, bool *do_rr)
 {
-       int m;
        bool match_do_rr = false;
+       bool rc = false;
+       int m;
 
-       if (rt->fib6_nh.fib_nh_flags & RTNH_F_DEAD)
+       if (nh->fib_nh_flags & RTNH_F_DEAD)
                goto out;
 
-       if (ip6_ignore_linkdown(rt->fib6_nh.fib_nh_dev) &&
-           rt->fib6_nh.fib_nh_flags & RTNH_F_LINKDOWN &&
+       if (ip6_ignore_linkdown(nh->fib_nh_dev) &&
+           nh->fib_nh_flags & RTNH_F_LINKDOWN &&
            !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
                goto out;
 
-       if (fib6_check_expired(rt))
-               goto out;
-
-       m = rt6_score_route(&rt->fib6_nh, rt->fib6_flags, oif, strict);
+       m = rt6_score_route(nh, fib6_flags, oif, strict);
        if (m == RT6_NUD_FAIL_DO_RR) {
                match_do_rr = true;
                m = 0; /* lowest valid score */
@@ -659,16 +656,16 @@ static struct fib6_info *find_match(struct fib6_info *rt, int oif, int strict,
        }
 
        if (strict & RT6_LOOKUP_F_REACHABLE)
-               rt6_probe(&rt->fib6_nh);
+               rt6_probe(nh);
 
        /* note that m can be RT6_NUD_FAIL_PROBE at this point */
        if (m > *mpri) {
                *do_rr = match_do_rr;
                *mpri = m;
-               match = rt;
+               rc = true;
        }
 out:
-       return match;
+       return rc;
 }
 
 static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
@@ -678,6 +675,7 @@ static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
                                     bool *do_rr)
 {
        struct fib6_info *rt, *match, *cont;
+       struct fib6_nh *nh;
        int mpri = -1;
 
        match = NULL;
@@ -688,7 +686,12 @@ static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
                        break;
                }
 
-               match = find_match(rt, oif, strict, &mpri, match, do_rr);
+               if (fib6_check_expired(rt))
+                       continue;
+
+               nh = &rt->fib6_nh;
+               if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
+                       match = rt;
        }
 
        for (rt = leaf; rt && rt != rr_head;
@@ -698,14 +701,25 @@ static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
                        break;
                }
 
-               match = find_match(rt, oif, strict, &mpri, match, do_rr);
+               if (fib6_check_expired(rt))
+                       continue;
+
+               nh = &rt->fib6_nh;
+               if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
+                       match = rt;
        }
 
        if (match || !cont)
                return match;
 
-       for (rt = cont; rt; rt = rcu_dereference(rt->fib6_next))
-               match = find_match(rt, oif, strict, &mpri, match, do_rr);
+       for (rt = cont; rt; rt = rcu_dereference(rt->fib6_next)) {
+               if (fib6_check_expired(rt))
+                       continue;
+
+               nh = &rt->fib6_nh;
+               if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
+                       match = rt;
+       }
 
        return match;
 }